/*********************************************************************
 *
 *  elksip - a multi-platform Sip Phone Server
 *
 *  file: rfc2617.c  rfc2617 hash
 *
 *  Copyright 2011-2013 Elksip.
 *
 ********************************************************************/

#ifdef HAVE_SSL
	#include <openssl/md5.h>
	#define  MD5Init  MD5_Init
	#define MD5Update MD5_Update
	#define MD5Final MD5_Final
#else
	#include"global.h"
	#include"md5.h"
#endif
#include<stdio.h>
#include<string.h>
#include "rfc2617.h"

#ifndef WIN32
  #define stricmp strcasecmp
#endif



void CvtHex(
    IN HASH Bin,
    OUT HASHHEX Hex
    )
{
    unsigned short i;
    unsigned char j;

    for (i = 0; i < HASHLEN; i++) {
        j = (Bin[i] >> 4) & 0xf;
        if (j <= 9)
            Hex[i*2] = (j + '0');
         else
            Hex[i*2] = (j + 'a' - 10);
        j = Bin[i] & 0xf;
        if (j <= 9)
            Hex[i*2+1] = (j + '0');
         else
            Hex[i*2+1] = (j + 'a' - 10);
    };
    Hex[HASHHEXLEN] = '\0';
};


/* calculate H(A1) as per spec */
void DigestCalcHA1(
    IN char * pszAlg,
    IN char * pszUserName,
    IN char * pszRealm,
    IN char * pszPassword,
    IN char * pszNonce,
    IN char * pszCNonce,
    OUT HASHHEX SessionKey
    )
{
      MD5_CTX Md5Ctx;
      HASH HA1;

      MD5Init(&Md5Ctx);
      MD5Update(&Md5Ctx, (unsigned char *)pszUserName, strlen(pszUserName));
      MD5Update(&Md5Ctx, (unsigned char *)":", 1);
      MD5Update(&Md5Ctx, (unsigned char *)pszRealm+1, strlen(pszRealm)-2);
      MD5Update(&Md5Ctx, (unsigned char *)":", 1);
      MD5Update(&Md5Ctx, (unsigned char *)pszPassword, strlen(pszPassword));
      MD5Final(HA1, &Md5Ctx);
      if (stricmp(pszAlg, "md5-sess") == 0) {
					  MD5Init(&Md5Ctx);
					  MD5Update(&Md5Ctx, HA1, HASHLEN);
					  MD5Update(&Md5Ctx, (unsigned char *)":", 1);
					  MD5Update(&Md5Ctx, (unsigned char *)pszNonce, strlen(pszNonce));
					  MD5Update(&Md5Ctx, (unsigned char *)":", 1);
					  MD5Update(&Md5Ctx, (unsigned char *)pszCNonce, strlen(pszCNonce));
					  MD5Final(HA1, &Md5Ctx);
	 };
	 CvtHex(HA1, SessionKey);
     printf("user:%s\n",pszUserName);
     printf("pszPassword:%s\n",pszPassword);
     printf("pszRealm:%s\n",pszRealm);
     printf("H1:%s\n",SessionKey);

};

/* calculate request-digest/response-digest as per HTTP Digest spec */
void DigestCalcResponse(
    IN HASHHEX HA1,           /* H(A1) */
    IN char * pszNonce,       /* nonce from server */
    IN char * pszNonceCount,  /* 8 hex digits */
    IN char * pszCNonce,      /* client nonce */
    IN char * pszQop,         /* qop-value: "", "auth", "auth-int" */
    IN char * pszMethod,      /* method from the request */
    IN char * pszDigestUri,   /* requested URL */
    IN HASHHEX HEntity,       /* H(entity body) if qop="auth-int" */
    OUT HASHHEX Response      /* request-digest or response-digest */
    )
{

      MD5_CTX Md5Ctx;
      HASH HA2;
      HASH RespHash;
      HASHHEX HA2Hex;

      // calculate H(A2)
      MD5Init(&Md5Ctx);
      MD5Update(&Md5Ctx, (unsigned char *)pszMethod, strlen(pszMethod));
      MD5Update(&Md5Ctx, (unsigned char *)":", 1);
      MD5Update(&Md5Ctx, (unsigned char *)pszDigestUri, strlen(pszDigestUri));
      if (pszQop!=NULL && stricmp(pszQop, "auth-int") == 0) {
            MD5Update(&Md5Ctx, (unsigned char *)":", 1);
            MD5Update(&Md5Ctx, (unsigned char *)HEntity, HASHHEXLEN);
      };
      MD5Final(HA2, &Md5Ctx);
       CvtHex(HA2, HA2Hex);
      printf("HA2:%s\n", HA2Hex);

      // calculate response
      MD5Init(&Md5Ctx);
      MD5Update(&Md5Ctx, (unsigned char *)HA1, HASHHEXLEN);
      MD5Update(&Md5Ctx, (unsigned char *)":", 1);
      MD5Update(&Md5Ctx, (unsigned char *)pszNonce+1, strlen(pszNonce)-2);
      MD5Update(&Md5Ctx, (unsigned char *)":", 1);
      if (pszQop) {

				MD5Update(&Md5Ctx, (unsigned char *) pszNonceCount, strlen(pszNonceCount));
				MD5Update(&Md5Ctx, (unsigned char *)":", 1);
				MD5Update(&Md5Ctx, (unsigned char *)pszCNonce, strlen(pszCNonce));
				MD5Update(&Md5Ctx, (unsigned char *)":", 1);
				MD5Update(&Md5Ctx, (unsigned char *)pszQop, strlen(pszQop));
				MD5Update(&Md5Ctx, (unsigned char *)":", 1);
	};
	MD5Update(&Md5Ctx, (unsigned char *)HA2Hex, HASHHEXLEN);
	MD5Final(RespHash, &Md5Ctx);
	CvtHex(RespHash, Response);

    printf("pszNonce:%s\n", pszNonce);
    printf("Response:%s\n", Response);
     
};

